[Risk factors for pneumonia, bacteremia, and urinary tract infection in an intensive care unit].
BACKGROUND
To identify nosocomial infection risk factors in an intensive care unit and construct a predictive model that will enable future risk-adjusted comparisons of infection incidences.


METHODS
Prospective surveillance of pneumonia, bacteremia and urinary tract infections in intensive care unit patients. All patients (n = 944) admitted to the intensive care unit for at least 24 h were followed daily in a tertiary level hospital. Variables measuring extrinsic as well as intrinsic risk factors for nosocomial infections were collected from each patient during their intensive care unit stay and the Cox proportional hazards multivariable technique was applied to identify the variables mostly associated with infection in our hospital.


RESULTS
The main risk factors identified for pneumonias were intrinsic. The hazard ratios (HR) of two extrinsic risk factors were noteworthy: mechanical ventilation (HR = 7.51; 95% CI = 2.95-19.13) and sedation (HR = 2.01; 95% CI = 1.14-3.56). The extrinsic factors associated with bacteremias were, the sum of extrinsic risk factors (HR = 1.52; 95% CI = 1.17-1.97) and having a tracheostomy (HR = 3.61; 95% CI = 1.99-6.56). The urinary tract infections were negatively associated with the administration of antibiotics prior to infection onset (HR = 0.41; 95% CI = 0.21-0.78) and the male sex (HR = 0.40; 95% CI = 0.22-0.75). Conversely, urinary tract infections were positively associated with the presence of cancer (HR = 2.70; 95% CI = 1.03-7.11) and the APACHE II index (for every 5 units of increase of the APACHE II index, HR = 1.39; 95% CI = 1.09-1.79).


CONCLUSIONS
The most important risk factors identified for pneumonias and urinary tract infections in intensive care unit patients were endogenous, whereas they were exogenous for bacteremias.
de Irala Estévez
J
J
Cátedra de Medicina Preventiva y Salud Pública, Facultad de Medicina, Universidad de Córdoba.
Fernández-Crehuet Navajas
R
R
Díaz Molina
C
C
Martínez de la Concha
D
D
Salcedo Leal
I
I
Masa Calles
J
J
D016470:Bacteremia / Q000453:epidemiology*; D003428:Cross Infection / Q000453:epidemiology*; D005260:Female; D006801:Humans; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011014:Pneumonia / Q000453:epidemiology*; D016016:Proportional Hazards Models; D012307:Risk Factors; D014552:Urinary Tract Infections / Q000453:epidemiology*
Factores de riesgo de neumonía, bacteriemia e infección urinaria en una unidad de cuidados intensivos.